use the service have a fear of bridges. Because the bridge normally only allows motor vehicles, bicyclists and snowmobiles shuttled across are subject to fees. The authority maintains a small police department to patrol the bridge and escort vehicles across, and a pair of radio station transmitters that broadcast bridge conditions and travel information on AM 530 and AM 1610. Upper Peninsula North of the Mackinac Bridge, I-75 passes to the west of downtown St. Ignace, traveling between the Father Marquette National Memorial and Straits State Park. There is an interchange north of the toll plaza that marks the eastern end of US 2 in the state and the southern end of BL I-75. The LMCT departs I-75 to follow US 2 while the LHCT follows BL I-75 through town. The freeway curves around Chain Lake and the Mackinac County Airport and meets the northern end of the business loop near Castle Rock; the LHCT returns to I-75 at that interchange as well. Continuing northward, M-123 (Tahquamenon Trail) intersects from the west as the freeway parallels H-63 (Mackinac Trail), the former route of US 2. I-75 crosses the Carp River and follows the shores of St. Martin Bay before meeting M-134. At that interchange, the LHCT departs again to run eastward. Through this area, the freeway continues northeasterly, traversing the Eastern Unit of the Hiawatha National Forest. I-75 crosses the Pine River before entering Chippewa County. The freeway takes a more northerly track as it travels under M-48 without an interchange. Farther north, M-48 curves around to connect I-75 with Rudyard, and the freeway turns back to continue northeastward. About northeast of Rudyard, I-75 passes next to Chippewa County International Airport, the former Kincheloe Air Force Base in Kinross and Kincheloe. North of there in Dafter, the freeway intersects M-28 (9 Mile Road). Beyond that interchange, I-75 picks up the Lake Superior Circle Tour (LSCT) designation, which it carries the rest of the way north. On the south side of Sault Ste. Marie, the freeway meets BS I-75 and picks up the LHCT designation one more time. I-75 rounds the west side of the city, passes the Sault Ste. Marie Municipal Airport and the campus of Lake Superior State University before meeting the customs and toll plazas for the International Bridge. From there, I-75 crosses the two-lane bridge and terminates at the Canadian border. , the toll rates on the